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The Straub Push-In Flex Coupling enables connections for a vast range of pipe diameters, pipe materials, media, temperatures, and operating pressures.

A progressive sealing effect increases the force on the sealing lips as the pressure in the pipe increases. The anchoring and sealing functions are also independent from each other, giving the pipework flexibility at every joint.

Straub Push-In Flex Couplings can be used on plain-ended pipes without any modifications. They can also be detached for storage or reuse.

The Flex 1L model comes in a size range of 48.3–168.3mm while Flex 2 is available from 172–2032mm.

Technical specifications




Flex 1L
Flex 2

Size range

Flex 1L: 48.3–168.3mm
Flex 2: 172–2032mm

Pressure range

Flex 1L: 16 bar
Flex 2: PN2.5, PN6, PN10, PN16, PN20, PN25

Material specifications


Flex 1L: AISI 316 L or similar
Flex 2: S355MC hot-dip galvanised, AISI 316 L or similar


AISI 4135, A4-80


AISI 12L14 galvanised
AISI 316 L or similar

Strip insert

Flex 1L: AISI 316 L or similar/PVDF
Flex 2: AISI 316 L or similar/HDPE

Sealing sleeve and temperature range

EPDM (-20°C to +100°C)
NBR (-20°C to +80°C)

How we help you select your SPI package:

1. Tell us what you need

Tell us about your project. What items are on your MTO list, and what options do you need to weigh up?

2. Choose the right solution

Weigh up the options. We'll do the analysis, discuss the options with you, and recommend the right products—the choices we'd make in your shoes.

3. Get the job done

You get the complete package delivered to site as ordered. The right price, reliable delivery, and everything to spec. No surprises.

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